1. Field of the Invention
The present embodiments relate generally to Wavelength Beam Combining (WBC) systems and methods for improving the desired output power turn-on time.
2. Description of the Prior Art
When diode emitters or elements are used in WBC systems they have the advantage of generally being more efficient than all other types of lasers. However, if the diode elements or emitters are not chosen or designed properly the output power turn-on time can be slow, such as ranging from milli-seconds (ms) to several seconds. For material processing this not desirable and often the output power turn-on time needs to be in the micro-second time range. These challenges are compounded when an increased power or high-power output is desired that requires combining multiple emitters.
Applicant has recognized that diode emitters operating in WBC systems will encounter slow turn-on time output power if not designed properly. This turn-on time problem is due to the fact that when the laser system is turned on from zero output power to full operating power there is a large thermal induced gain shift at the junction of the diode emitters. At zero output power the junction temperature of the diode emitters is essentially the same temperature as the heat sink or coolant temperature. At the full operating power the junction temperature will increase. This change in junction temperature will shift the gain of the diode elements accordingly. If the shift of the gain peak is larger than the gain bandwidth of the diode elements than the output power turn-on time will be slow.